Objective: With advantages of reduced coupling and compact structure, Matrix Coils (MCs) design extension to approximate multiple target inhomogeneities is necessary to improve its performance in shimming applications.
Methods: A Spherical Harmonics Decomposition Method (SHDM) is proposed for the multi-target MCs optimization problem. The magnetic field generated by the MCs is represented in form of SHs' orthogonal basis, based on which the MCs pattern is optimized to adapt to multiple SH targets.
Results: With multi-target SHs of the 1, 3 and mixed 1&2 degrees in Halbach magnet shimming, MCs structure optimizations were successfully performed. Comparisons with regular interleaved MCs show the optimized coil structure provides better performance, including reduction of power dissipation, maximum current amplitude, and total current requirement.
Conclusion: This work proposed a simple and intuitive way of irregular MCs optimization, which is of high benefits in compact MR systems based on permanent magnets.
Significance: This methodology may also be translated into local gradient & shimming matrix coils designs for conventional magnetic resonance device.
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http://dx.doi.org/10.1109/TBME.2021.3111656 | DOI Listing |
Magn Reson Imaging
January 2025
Vanderbilt University Institute of Imaging Science, Vanderbilt University Medical Center, Nashville, TN 37232, USA; Department of Radiology and Radiological Sciences, Vanderbilt University Medical Center, Nashville, TN 37232, USA; Department of Electrical and Computer Engineering, Vanderbilt University, Nashville, TN 37232, USA. Electronic address:
Background: Inductively coupled wireless coils are increasingly used in MRI due to their cost-effectiveness and simplicity, eliminating the need for expensive components like preamplifiers, baluns, coil plugs, and coil ID circuits. Existing tools for predicting component values and electromagnetic (EM) fields are primarily designed for cylindrical volume coils, making them inadequate for irregular volume-type wireless coils.
Purpose: The aim of this study is to introduce and validate a novel magnetic (H-) field probe-based co-simulation method to accurately predict capacitance values and EM fields for irregular volume-type wireless coils, thereby addressing the limitations of current prediction tools.
Matrix Biol
January 2025
Manchester Cell-Matrix Centre, Division of Cell-Matrix Biology and Regenerative Medicine, School of Biological Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester Academic Health Science Centre, Manchester M13 9PT, UK; Lydia Becker Institute of Immunology and Inflammation, University of Manchester, Manchester, M13 9PL, United Kingdom. Electronic address:
Pentraxin-3 (PTX3) is an octameric protein, comprised of eight identical protomers, that has diverse functions in reproductive biology, innate immunity and cancer. PTX3 interacts with the large polysaccharide hyaluronan (HA) to which heavy chains (HCs) of the inter-α-inhibitor (IαI) family of proteoglycans are covalently attached, playing a key role in the (non-covalent) crosslinking of HC•HA complexes. These interactions stabilise the cumulus matrix, essential for ovulation and fertilisation in mammals, and are also implicated in the formation of pathogenic matrices in the context of viral lung infections.
View Article and Find Full Text PDFBiomedicines
December 2024
Department of Ophthalmology, School of Medicine, Sapporo Medical University, S1 W16 Chuo-ku, Sapporo City 060-8543, Hokkaido, Japan.
Background/objectives: The objective of the present study was to examine the unidentified effects that RHO-associated coiled-coil-containing protein kinase 1 and 2 antagonists exert on the transforming growth factor beta2-induced epithelial-mesenchymal transition of the human corneal stroma.
Methods: In the presence or absence of pan-RHO-associated coiled-coil-containing protein kinase inhibitors, ripasudil or Y27632 and RHO-associated coiled-coil-containing protein kinase 2 inhibitor, KD025, we analyzed the following: (1) planar proliferation caused by trans-endothelial electrical resistance and the cellular metabolic characteristics of the two-dimensional cultures of human corneal stroma fibroblasts; (2) the physical properties of a three-dimensional human corneal stroma fibroblasts spheroid; and (3) the gene expressions and their regulators in the extracellular matrix, along with the tissue inhibitors of metalloproteinases and matrix metalloproteinases and the endoplasmic reticulum stress-related factors of the two-dimensional and three-dimensional cultures in human corneal stroma fibroblasts.
Results: Exposure to 5 nM of the transforming growth factor beta2 markedly increased the trans-endothelial electrical resistance values as well as the metabolic function in two-dimensional cultures of human corneal stroma fibroblasts.
Cell Biosci
December 2024
Department of Biological and Environmental Sciences and Technologies (DiSTeBA), University of Salento, Lecce, Italy.
N-myc downstream-regulated gene 1 (NDRG1) is a member of the NDRG family of intracellular proteins and plays a central role in a wide range of biological processes including stress response, differentiation, and metabolism. The overexpression of NDRG1 is an indicator of poor prognosis in various types of cancer. Here, we found that NDRG1 is an independent prognostic marker of poor outcome in breast cancer (BC).
View Article and Find Full Text PDFHeliyon
July 2024
Sir Peter Mansfield Imaging Centre, School of Physics and Astronomy, University of Nottingham, Nottingham, NG7 2RD, UK.
Prospective motion corrections in brain imaging for MRI are fairly challenging. Monitoring involuntary head movement inside MR scanner is crucial for prospective motion correction. This initial study delves into utilizing simulations to track the head's movements within an MRI scanner, achieved by measuring induced voltage changes from time-varying magnetic field gradients in head-mounted coils.
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